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Inapprorpriate Rejection for HCV Therapy for Psychiatric Disorder
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"Utility of a depression score to predict candidacy for hepatitis C virus therapy in veterans: a prospective longitudinal study"
Alimentary Pharmacology & Therapeutics
Volume 21 Issue 3 Page 235 - February 2005
This study finds that patients who were initially rejected for HCV therapy because they had psychiatric disorders could be given a test to diagnose depression & receive HCV therapy. Depression in HCV+ individuals can be treated with anti-depressants. In other words, these patients were initially misdiagnosed & therefore inappropriately rejected for HCV therapy.
"...By the end of follow-up, 42 of 145 (29%) patients who were initially ineligible because of psychiatric disorders became eligible and received IFN-based HCV antiviral therapy...Patients with a known psychiatric diagnosis were eligible to receive HCV treatment if their treating psychiatrist believed in their ability to tolerate interferon without significant risk of suicide or extreme depression...
... We found a high prevalence of psychiatric disorders among HCV-infected patients. Importantly, approximately half of these patients did not carry a previous psychiatric diagnosis and were only detected by elevated Zung SDS. This instrument was easy to administer and was associated with a high validity in comparison to a formal psychiatric evaluation. Subsequent referral and management of HCV-infected patients with mood disorders was associated with eligibility of approximately one-quarter of these patients during a follow up that lasted slightly over 2 years. Patients with severe mood disorder as indicated by an SDS score >70 were highly unlikely (only 2%) to receive therapy even after referral and management by psychiatrist..."
Authors: S. Tavakoli-Tabasi*, P. Rowan*, + , M. Abdul-Latif , M. E. Kunik*, + & H. B. El-Serag*
*The Houston Veterans Affairs Medical Center, Baylor College of Medicine, Department of Medicine; +Veterans Affairs South Central Mental Illness Research, Education, and Clinical Centers, The Houston Center for Quality of Care and Utilization Studies, Department of Psychiatry and Behavioral Sciences at Baylor College of Medicine; University of Saint Thomas, Houston, TX, USA
Summary
Background: The frequency and determinants of receipt of antiviral therapy once a diagnosis of a mood disorder is established in hepatitis C virus (HCV)-infected patients remains unknown.
Aim: To examine the incidence and determinants of receiving antiviral therapy in HCV-infected veterans with abnormal scores of Zung Self-Rating Depression Scale (SDS).
Methods: We systematically evaluated the presence of psychiatric disorders among HCV-infected patients with initial referral between September 2000 and May 2002. We reviewed medical records, obtained history, and administered Zung SDS to evaluate for depressive symptoms. Patients with psychiatric disorders were referred for psychiatric evaluation. The primary outcome was the receipt of antiviral therapy during and after the initial evaluation up to December 1, 2003. The association between SDS scores and receipt of antiviral therapy was examined in a multivariate Cox proportional hazards regression.
The Zung SDS takes approximately 10 min to complete. Scores from questionnaires were used for clinical decision-making, therefore they were checked for completeness during the same visit.
Results: A total of 424 patients completed a Zung SDS. The scores were normal in only 43% of all patients, and were impaired mildly in 25%, moderately in 23%, and severely in 9%. Zung SDS scores were significantly higher in patients who served during the Vietnam War era, participated in combat, or had lower albumin levels. At the end of the first visit, 180 (42%) had psychiatric disorders. An abnormal Zung score (>55) was the only reason for referral to psychiatry in 83 of 180 patients; and in those 78 (94%) a formal psychiatric evaluation confirmed depressive disorder. Psychiatric disorders were the sole contraindication to therapy in 145 (34%) patients in whom eligibility for antiviral therapy was achieved in 42 (29%) during a mean follow-up duration of 27 months.
Conclusions: Approximately one-quarter of patients with psychiatric disorders may become eligible for antiviral therapy following subsequent management of these disorders. The Zung self-screening test is an easy, valid method for detecting mood disorders in HCV-infected veterans.
AUTHOR DISCUSSION
We found a high prevalence of psychiatric disorders among HCV-infected patients. Importantly, approximately half of these patients did not carry a previous psychiatric diagnosis and were only detected by elevated Zung SDS. This instrument was easy to administer and was associated with a high validity in comparison to a formal psychiatric evaluation. Subsequent referral and management of HCV-infected patients with mood disorders was associated with eligibility of approximately one-quarter of these patients during a follow up that lasted slightly over 2 years. Patients with severe mood disorder as indicated by an SDS score >70 were highly unlikely (only 2%) to receive therapy even after referral and management by psychiatrist.
Our study supports the use of Zung SDS in HCV-infected patients, which until now has not been evaluated. A substantial proportion of patients with mood disorders were detected solely on the basis of abnormal Zung SDS (>55). In these patients, there was a strong correlation between elevated SDS score and the finding of a mood disorder by a psychiatrist; all but five of 82 patients referred solely on the basis of this score were independently confirmed by formal psychiatric evaluation. It is also important to note that there were no other historical data, or laboratory finding that could have predicted the presence of what proved to be clinically significant mood disorders in 78 (18%) of patients in this study detected by the Zung SDS.
Zung SDS findings are non-specific and are not meant to differentiate among different mood disorders, therefore, proper referral is required. As most physicians providing treatment for HCV are not primarily trained in psychiatric diagnosis and intervention, the use of validated symptoms questionnaires is advocated. The usefulness of other screening tools for depression among HCV-infected patients has been shown in other studies. 8 While many, such as the Center for Epidemiological Studies - Depression Scale, the Beck Depression Inventory-II, and the Zung SDS, perform similarly as screening instruments in medical settings, 21, 22 the Zung SDS may have advantages. First, it is not proprietary, so costs are low. Second, it is not limited to DSM-IV-specific symptomatology, so it may be more sensitive for detecting patients with elevated depressive symptoms, including those who do not meet formal criteria for a depressive disorder. Third, evidence suggests that the Zung SDS is sensitive to changes in depressive symptom level, including at milder symptom levels, 22,24 attributed partly to the equal balance of positively and negatively worded items. Finally, our experience has been that clinicians and patients both find it easy to use.
The severity of mood disorders, as indicated by high Zung SDS scores, was associated with military service during Vietnam era, participation in combat, and lower albumin levels. The finding of lower albumin in those with higher depression scores has been previously reported, likely reflecting the severity of liver disease and presence of liver synthetic dysfunction. There are at least two important findings that resulted from the prospective evaluation (mean surveillance time 27 months) of HCV-infected patients who were initially screened with the Zung SDS and denied antiviral therapy because of the presence of a mood disorder. The first finding is that psychiatric intervention resulted in 42 patients (29%) of patients with mental health disorders becoming eligible for antiviral therapy. Given that low eligibility rate is the major obstacle in the face of improving the effectiveness of HCV antiviral therapy, this finding has important implications. The use of a screening instrument for depression may lead to more rapid diagnosis, evaluation and treatment. The second finding is that the Zung SDS scores during the first interview were strongly predictive of the subsequent eligibility for HCV antiviral therapy. In the absence of other contraindications, a large proportion of patients without significant history of mental health disorders who have a Zung SDS of <=55 were safely started on antiviral therapy in our clinic. The higher Zung SDS, the less likely it was for the patients to be able to start antiviral therapy for hepatitis C. More than half of patients with mild impairment of Zung SDS were started on antiviral therapy, while only 2% those with Zung SDS scores above 70, indicative of severe mood disorder, became eligible for interferon-based treatments.
The results of the study must be interpreted within its limitations. It was conducted among veterans, mostly men, who receive their care at a VA health care system, and therefore the results may not be generalizable to non-veterans, women or to other health care settings. Having more men is likely to be reflected as increased prevalence of substance use disorders (men more than women). 25 On the other hand, having more African Americans in our study sample than the general population may have resulted in a disproportionate increase in psychosis and decrease in depression, although the racial differences in psychiatric disorders are not universally agreed upon. 26 In addition, the high prevalence of comorbid medical conditions, such as advanced cardiovascular and pulmonary disease may have limited our ability further to use antiviral therapy. This may not be reflective of all US population, however, this is in accordance with what has previously been found among patients with HCV in VA healthcare systems. 5-8
The Zung questionnaire screens only for symptoms of depression, and thus other psychiatric disorders may not been identified with the same accuracy. In addition, some patients who were euthymic at the time initial evaluation have significant history of mood disorders, such as major depressive disorder and bipolar disorder, and history of attempting suicide. In these patients Zung SDS, although normal, does not eliminate a need for a more detailed psychiatric evaluation. In our study, 18 patients had Zung SDS in the normal range, yet they were referred to psychiatry because of history of psychosis or attempted suicide (9.9% false negative rate). Clearly, Zung SDS should not be a replacement but rather a complement to a careful history of mental health disorders and special inquiry about suicide. Future studies should examine the use of a battery of questionnaires to screen for psychiatric disorders. One challenge for assessment of depression with a self-report screening instrument is the application in patients with medical disorders. Depressive symptomatology overlaps with somatic symptomatology, including sleep disturbance, changed appetite, lowered libido and fatigue. However, an investigation of this issue 27 indicated that, despite the somatic item content of the SDS, scores had a weak correlation with physician rating of physical heath (obtained r =0.19, P > 0.01). Lastly, in the absence of a control group it may not be appropriate to attribute the receipt of antiviral therapy following the initial evaluation to the diagnosis and management of mood disorders. Unrelated patient and provider factors could have contributed to some of these cases over the course of the 2-year follow-up.
The current study also has several strengths. To our knowledge, this is largest study to prospectively evaluate the prevalence of mood disorders among HCV-infected patients using a validated screening questionnaire. Therefore the prevalence estimates of mood disorders obtained have a relatively high degree of validity as well as precision. The follow-up information was available for the great majority of participants, and was relatively long coupled with a frequent number of outcomes (n = 42), thus allowing us to conduct adequate statistical examination of at least four potential predictors at a time in logistic regression and Cox OH models. Lastly, the readily available psychiatric consultation within the VA system was a crucial component of the study and allowed for referral of virtually all patients with diagnosed or suspected psychiatric disorders.
In conclusion, we recommend the use of validated questionnaires to screen for mood disorders in HCV-infected patients. In our experience reported in this study, the use of Zung SDS has been an easy and valid method. Lastly, we strongly recommend referral and management of patients with mood disorders as at least a quarter of these patients may become eligible for antiviral therapy within a relatively short time.
RESULTS
From September 2000 to May 2002, 498 patients were referred to the HCV Clinic at the MEDVAMC. Seventy-four patients were excluded from the study because of the absence of detectable HCV-RNA on qualitative PCR test. The study included 424 patients. Table 1 illustrates the characteristics of the study population. Only 76 (18%) of 424 were eligible and went on to receive HCV antiviral therapy following the initial evaluation. During follow-up till December 1, 2003, an additional 52 patients (12%) received antiviral therapy. Table 2 illustrates the outcomes of the 424 patients at the end of the study.
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As shown in Figure 1 (see figure below), at least one psychiatric disorder was recorded in 180 of 424 (42.5%) patients during the initial evaluation. Ninety-seven of these 180 patients (53.8%) were previously diagnosed with a psychiatric condition according to medical records or history taking (appear in three separate categories of 10, 79, and eight patients in Figure 1). In the remaining 83 (46.2%) patients, depression was suspected based on a Zung SDS score >55 alone. Among the 180 patients who were initially ineligible for antiviral therapy because of a mental health disorder diagnosis, 19 had permanent contraindications to interferon-based therapy because of advanced medical conditions. Thus, there were 161 patients in whom the main obstacle to antiviral therapy was a mental health disorder; these patients were consequently referred to psychiatry. Eleven were non-adherent, failing to attend either the psychiatric evaluation or subsequent hepatitis C clinic visits. Five patients, who were referred to psychiatry because of a Zung SDS >55, were found to have no mental heath disorder following a formal psychiatric evaluation. The most frequent psychiatric diagnoses for the 145 patients who were evaluated by psychiatrist were mood disorders (61%), anxiety/post-traumatic stress disorder (PTSD) (12%), or substance induced mood disorder (13%). The mean duration of follow-up was 27 months (range: 19-40 months). By the end of follow-up, 42 of 145 (29%) patients who were initially ineligible because of psychiatric disorders became eligible and received IFN-based HCV antiviral therapy.
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Of the 424 HCV-infected patients, Zung SDS scores were within the normal range for 182 (42.9%), and abnormal in 244 (57.1%) (Figure 1). Abnormal scores were indicative of minimal to mild mood disorder in 108 (25.5%), moderate in 98 (22.6%), and severe in 38 (9.0%). Among the 108 patients with minimal to mild depression 26 had a Zung SDS of >55 and were referred for psychiatric evaluation, while of the rest (82 patients) had Zung SDS of 50-55 and of those only eight, in whom a previous diagnosis of mental health disorder existed, were referred for psychiatric evaluation. All patients with a Zung SDS consistent with moderate or severe depression were referred to psychiatry (Figure 1). All but five of 83 patients referred to psychiatric evaluation for SDS score >55 alone were found to have a mental health disorder according to the evaluating psychiatrist. On the other hand, 18 patients with Zung SDS scores <=55 were initially ineligible for interferon therapy because of a history of severe mental health disorders, which was later confirmed by psychiatric evaluation. Zung SDS scores were not significantly associated with race, gender, risk factors for HCV infection, years of heavy alcohol consumption, AST and ALT levels, HCV viral load, platelet count, prothrombin time, or alpha-fetoprotein levels. It only showed significant weak negative correlation with albumin levels (r = 0.11, P = 0.03), and non-significant negative correlation with age. Abnormally high Zung SDS had a significant positive association with history of military combat and military service during Vietnam era.
Zung SDS scores were analyzed in relation to receiving antiviral therapy. There was a significant progressive decrease in the proportion of patients who received antiviral therapy among groups with no depression, mild, moderate and severe depression (P for linear trend <0.001). Only two of 38 (5.3%) patients with a Zung SDS score of >=70 became eligible for treatment while 40 of 142 (28.2%) patients with Zung SDS of <70 became eligible for IFN-based regimen. For patients with mild or moderate depression, these proportions were 30.6 and 26.8%, respectively.
We constructed multivariate logistic regression models to examine the possible predictors of receiving interferon treatment at any time after the initial evaluation visit (n = 128). The primary determinant was Zung SDS scores (Table 3). Cox proportional hazards models were also constructed to examine the determinants of the time to receiving interferon treatment after the initial evaluation visit. Four levels of SDS scores were considered: normal (<50), mild (50-59), moderate (60-69) or severe (>70). Results are presented in Table 4. In both models, neither sex nor race/ethnicity were associated with receiving therapy. Only a high Zung SDS score and older age were predictive of not receiving antiviral treatment. For example, in the logistic regression analyses, contrasted with patients who had normal SDS scores, patients with 'moderate' SDS scores were approximately half as likely to receive treatment, and patient with 'severe' SDS scores were only a tenth as likely to receive treatment.
Introduction
Hepatitis C virus (HCV) infection is the major cause of chronic hepatitis in the United States. 1, 2 Recent studies have shown that most of HCV-infected patients are not treated with current standard interferon (IFN)-based antiviral therapy. 3-5 Comorbid psychosocial conditions are the most common reasons preventing initiation and successful completion of antiviral therapy among HCV-infected veterans. 5-9 In addition, achieving sustained viral response with antiviral therapy in clinical practice may be less likely than what was reported in the clinical trials. 5, 10
The prevalence of psychiatric disorders (with focus on disorders of mood) among HCV-infected veterans has been evaluated by several studies. These studies were either retrospective analyses of administrative datasets, medical records review, 7, 11 prospective evaluations of depression by using trained personnel, 12 or validated screening questionnaires for depression, 6, 8 with or without medical chart review.
The available studies do not offer information on the subsequent clinical course of mood disorders among HCV-infected patients initially ineligible for antiviral therapy because of the presence of depressed/unstable mood. Some studies suggested that depression should not be considered an absolute contraindication for interferon-based therapy. 13 However, there is little information on frequency or the determinants of receipt of antiviral therapy once a diagnosis of a mood disorder is established. It is important for clinicians who treat HCV infection to have tools that allow them to screen for the presence and severity of mood disorders, and to be able to prognosticate the likelihood of response of these disorders to the point when interferon-based therapies could be initiated. Thus there is a need for studies that identify mood disorders using valid measures in large samples of HCV-infected patients and prospectively show that an improvement of the symptoms of chronic mood disorders would lead to therapy.
The Zung Self-rating Depression Scale (SDS) 14 has been used, and extensively validated, for the detection and follow up of mood disorders. 9, 15-19 In this study we used Zung SDS in large sample of HCV-infected patients to identify mood disorders, which were subsequently confirmed with formal psychiatric evaluation. These patients were then prospectively evaluated for receipt of antiviral therapy following psychiatric evaluation and treatment. We hypothesized that Zung SDS will be helpful in identifying otherwise not diagnosed depression and that the score obtained at baseline will predict future eligibility for INF-based therapy.
Methods
Study subjects
This was a prospective study among patients who tested positive for HCV by ELISA serology and were consecutively referred to the HCV Clinic at the Michael E. DeBakey Veterans Affairs Medical Center (MEDVAMC) between September 2000 and May 2002. For this analysis, patients were followed till December 1, 2003.
During the initial assessment, the diagnosis of HCV was confirmed by HCV-RNA assay. A standardized history and physical examination was conducted to collect demographic features, and medical and psychiatric history. Race/ethnicity was self-reported, and classified as White non-Latino, African-American or Latino. Military history was assessed for period of service as well as participation in combat. History of exposure to HCV risk factors was collected during the first clinic visit, including injection drug use (IDU), blood or blood product transfusion, intranasal use of cocaine; tattoos; body piercing; multiple sexual partners; or haemodialysis. Laboratory data were accessed through the MEDVAMC computerized patient recording system (CPRS). HCV qualitative and quantitative PCR assays were performed by Roche Amplicor Assay. HCV genotyping was performed using Innogenetics LiPA HCV II assay. 'Years of heavy drinking' was defined as the number of years patients were drinking more than 20 drinks a week on a continuous basis.
Evaluation for psychiatric disorders was conducted by one staff physician during the first visit to the hepatitis C clinic and consisted of medical records review, personal inquiry about history of diagnosed psychiatric disorders, personal inquiry about depressive symptoms or suicidal ideation, and completion of a Zung SDS. Zung SDS is a tool that screens for the presence of depressive symptoms. SDS items pertain to affective symptomatology (e.g. feeling downhearted), psychological symptomatology (e.g. self-perceptions of being useless) and physiological symptomatology (e.g. disturbed sleep or appetite). For each of 20 statements (e.g., 'I feel down-hearted and blue'), patients endorse the most fitting of four responses that range from 'a little of the time' to 'most of the time.' The least severe response is scored 1 and the most severe response is scored 4. Scores are summed and then divided by the maximum score of 80 in order to obtain a quantitative index of depressive symptomatology (SDS) that ranges from 25 to 100. Zung has ascribed the following categories: 50-59 = minimal to mild depression; 60-69 = moderate-marked depression; >=70 = severe-extreme depression. 18 We employed a cut score of 55, indicating a mild level of depressive symptoms, to delay IFN treatment and to prompt a psychiatric referral. The Zung SDS takes approximately 10 min to complete. Scores from questionnaires were used for clinical decision-making, therefore they were checked for completeness during the same visit.
All patients with a past or present history of psychiatric disorders (obtained from history and medical charts) who were not under the care of a mental health provider, or a Zung SDS > 55 were referred for complete psychiatry evaluation. Patients with a Zung SDS of 50-55 were referred to psychiatry only if they had additional history of mental health disorders. Patients were only considered eligible for IFN-based therapy once evaluated by the psychiatrist and were deemed able to tolerate IFN. Each patient was given a follow-up appointment to the hepatitis C clinic 6 months from the initial evaluation. Patients who did not show up for their follow-up evaluation were rescheduled for up to two more appointments 1 month apart. Patients who were still not eligible for HCV antiviral therapy after the first 6-month follow-up period, based on the psychiatrist evaluation, were given follow up appointments at 6-month intervals. Each upcoming appointment was preceded by a reminder letter and reminder telephone call. The duration of the follow-up period was calculated from the date of the initial visit to the hepatitis C clinic for each patient to December 1, 2003, when the data were analyzed. Patients were evaluated by one of the two staff psychiatrists at Houston Veterans Affairs Medical Center. If patients were seen by residents or physician assistants, we required the supervising physician to confirm each diagnosis and impression in a written form.
Eligibility for antiviral therapy was defined in accordance with the Veterans Affairs Treatment Guidelines for patients with chronic HCV. 20 Eligible patients were offered standard antiviral therapy. Ineligibility criteria included the presence of decompensated cirrhosis, hepatocellular carcinoma, haematologic or solid organ malignancies that were not in remission, severe cardiac disease, chronic obstructive pulmonary disease with FEV1 < 1.0 L, autoimmune disorders, neutropenia (<1500 cells/cc), chronic anaemia with a haemoglobin level (<10 g/dL), and low platelet counts (<60 000/cc). Patients with a known psychiatric diagnosis were eligible to receive HCV treatment if their treating psychiatrist believed in their ability to tolerate interferon without significant risk of suicide or extreme depression.
Statistical analysis
Demographic, clinical, and laboratory test results were summarized as mean (and standard deviation), median, and ranges for continuous variables, and proportions for categorical variables. Using Pearsen correlation tests, we examined the relation between Zung SDS scores and several continuous variables including age, duration of HCV infection, years of heavy alcohol drinking, and serum levels of AST, ALT, prothrombin time, albumin, platelet count, HCV viral counts, and alpha fetoprotein. Chi-squared tests were used to examine the association between Zung SDS scores (as a categorical variable) and several categorical variables including gender, ethnicity, era of military service, combat experience, HCV acquisition risk factors, HCV genotype and the presence of HBsAg. Cox proportional hazard models were constructed to examine the effect of several demographic and clinical features as well as SDS scores on the likelihood of beginning IFN treatment. For all models, the number of covariates examined was determined by the number of outcome events with at least 10 events required for one covariate (23). P values less than 0.05 were considered statistically significant.
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